1. Field of the Invention
This invention relates generally to caps for hand-held dispensers, and more particularly to devices of the type which resist re-sealing, following initial use of the dispenser.
2. Description of the Related Art Including Information Disclosed Under 37 CFR .sctn..sctn.1.97-1.99
My U.S. Pat. No. 4,424,918 illustrates one type of non-resealable cap construction involving a turnable twist cap which is carried on a cap body, and where there are interference shoulders on the inner surface of the twist cap and on the cap body, which by-pass one another when the twist cap is initially raised, and which prevent it from being subsequently re-seated.
Typical cap constructions of the twist-open or push-pull type are disclosed in U.S. Pat. No. 3,351,249 issued Nov. 7, 1967, to M. B. Stull, and entitled CAPTIVE DISPENSING CLOSURE FOR CONTAINERS; and U.S. Pat. No. 1,958,429 issued May 15, 1934, to P. Hartog, and entitled CLOSURE FOR TUBES AND LIKE CONTAINERS. Both of the patented devices are intended to be resealable following each use.
U.S. Pat. Nos. 3,325,064; 4,277,004; and 4,440,325 disclose aerosol valve dispensers which contain detent structures that permit the valve to be initially opened and held in such open condition, either momentarily or else continuously, in the latter case it being desired to dispense completely the contents of the container. U.S. Pat. No. 3,804,302 relates to an aerosol valve having a safety mechanism permitting venting of residual gas from the container after its contents have been exhausted.
As noted in U.S. Pat. No. 4,424,918, there exist applications which dictate the use of a dispenser that cannot be resealed after initial use. The example cited is the case where two different substances are mixed together in a container, and which result in generation of gas that must be vented in order to avoid possible undesirable pressure build-up in the container.
It is believed that there exists a need for a relatively simple non-resealable cap which can be readily produced and which is low in manufacturing cost.